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GLENABLE

NAME
C SPECIFICATION
PARAMETERS
C SPECIFICATION
PARAMETERS
DESCRIPTION
NOTES
ERRORS
SEE ALSO

NAME

glEnable, glDisable − enable or disable server-side GL capabilities

C SPECIFICATION

void glEnable( GLenum cap )

PARAMETERS

cap

Specifies a symbolic constant indicating a GL capability.

C SPECIFICATION

void glDisable( GLenum cap )

PARAMETERS

cap

Specifies a symbolic constant indicating a GL capability.

DESCRIPTION

glEnable and glDisable enable and disable various capabilities. Use glIsEnabled or glGet to determine the current setting of any capability. The initial value for each capability with the exception of GL_DITHER is GL_FALSE. The initial value for GL_DITHER is GL_TRUE.

Both glEnable and glDisable take a single argument, cap, which can assume one of the following values:

	GL_ALPHA_TEST		If enabled, do alpha testing. See glAlphaFunc.
	GL_AUTO_NORMAL		If enabled, generate normal vectors when either GL_MAP2_VERTEX_3 or GL_MAP2_VERTEX_4 is used to generate vertices. See glMap2.
	GL_BLEND		If enabled, blend the incoming RGBA color values with the values in the color buffers. See glBlendFunc.
	GL_CLIP_PLANEi		If enabled, clip geometry against user-defined clipping plane i. See glClipPlane.
	GL_COLOR_LOGIC_OP		If enabled, apply the currently selected logical operation to the incoming RGBA color and color buffer values. See glLogicOp.
	GL_COLOR_MATERIAL		If enabled, have one or more material parameters track the current color. See glColorMaterial.
	GL_COLOR_TABLE		If enabled, preform a color table lookup on the incoming RGBA color values. See glColorTable.
	GL_CONVOLUTION_1D		If enabled, perform a 1D convolution operation on incoming RGBA color values. See glConvolutionFilter1D.
	GL_CONVOLUTION_2D		If enabled, perform a 2D convolution operation on incoming RGBA color values. See glConvolutionFilter2D.
	GL_CULL_FACE		If enabled, cull polygons based on their winding in window coordinates. See glCullFace.
	GL_DEPTH_TEST		If enabled, do depth comparisons and update the depth buffer. Note that even if the depth buffer exists and the depth mask is non-zero, the depth buffer is not updated if the depth test is disabled. See glDepthFunc and

glDepthRange.

	GL_DITHER		If enabled, dither color components or indices before they are written to the color buffer.
	GL_FOG		If enabled, blend a fog color into the posttexturing color. See glFog.
	GL_HISTOGRAM		If enabled, histogram incoming RGBA color values. See glHistogram.
	GL_INDEX_LOGIC_OP		If enabled, apply the currently selected logical operation to the incoming index and color buffer indices. See

glLogicOp.

	GL_LIGHTi		If enabled, include light i in the evaluation of the lighting equation. See glLightModel and glLight.
	GL_LIGHTING		If enabled, use the current lighting parameters to compute the vertex color or index. Otherwise, simply associate the current color or index with each vertex. See

glMaterial, glLightModel, and glLight.

	GL_LINE_SMOOTH		If enabled, draw lines with correct filtering. Otherwise, draw aliased lines. See glLineWidth.
	GL_LINE_STIPPLE		If enabled, use the current line stipple pattern when drawing lines. See glLineStipple.
	GL_MAP1_COLOR_4		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate RGBA values. See glMap1.
	GL_MAP1_INDEX		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate color indices. See glMap1.
	GL_MAP1_NORMAL		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate normals. See glMap1.
	GL_MAP1_TEXTURE_COORD_1		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s texture coordinates. See glMap1.
	GL_MAP1_TEXTURE_COORD_2		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s and t texture coordinates. See glMap1.
	GL_MAP1_TEXTURE_COORD_3		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s, t, and r texture coordinates. See glMap1.
	GL_MAP1_TEXTURE_COORD_4		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate s, t, r, and q texture coordinates. See glMap1.
	GL_MAP1_VERTEX_3		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate x, y, and z vertex coordinates. See glMap1.
	GL_MAP1_VERTEX_4		If enabled, calls to glEvalCoord1, glEvalMesh1, and glEvalPoint1 generate homogeneous x, y, z, and w vertex coordinates. See glMap1.
	GL_MAP2_COLOR_4		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate RGBA values. See glMap2.
	GL_MAP2_INDEX		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate color indices. See glMap2.
	GL_MAP2_NORMAL		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate normals. See glMap2.
	GL_MAP2_TEXTURE_COORD_1		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s texture coordinates. See glMap2.
	GL_MAP2_TEXTURE_COORD_2		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s and t texture coordinates. See glMap2.
	GL_MAP2_TEXTURE_COORD_3		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s, t, and r texture coordinates. See glMap2.
	GL_MAP2_TEXTURE_COORD_4		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate s, t, r, and q texture coordinates. See glMap2.
	GL_MAP2_VERTEX_3		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate x, y, and z vertex coordinates. See glMap2.
	GL_MAP2_VERTEX_4		If enabled, calls to glEvalCoord2, glEvalMesh2, and glEvalPoint2 generate homogeneous x, y, z, and w vertex coordinates. See glMap2.
	GL_MINMAX		If enabled, compute the minimum and maximum values of incoming RGBA color values. See glMinmax.
	GL_NORMALIZE		If enabled, normal vectors specified with glNormal are scaled to unit length after transformation. See glNormal.
	GL_POINT_SMOOTH		If enabled, draw points with proper filtering. Otherwise, draw aliased points. See glPointSize.
	GL_POLYGON_OFFSET_FILL		If enabled, and if the polygon is rendered in GL_FILL mode, an offset is added to depth values of a polygon’s fragments before the depth comparison is performed. See glPolygonOffset.
	GL_POLYGON_OFFSET_LINE		If enabled, and if the polygon is rendered in GL_LINE mode, an offset is added to depth values of a polygon’s fragments before the depth comparison is performed. See glPolygonOffset.
	GL_POLYGON_OFFSET_POINT		If enabled, an offset is added to depth values of a polygon’s fragments before the depth comparison is performed, if the polygon is rendered in GL_POINT mode. See glPolygonOffset.
	GL_POLYGON_SMOOTH		If enabled, draw polygons with proper filtering. Otherwise, draw aliased polygons. For correct anti-aliased polygons, an alpha buffer is needed and the polygons must be sorted front to back.
	GL_POLYGON_STIPPLE		If enabled, use the current polygon stipple pattern when rendering polygons. See glPolygonStipple.

GL_POST_COLOR_MATRIX_COLOR_TABLE

If enabled, preform a color table lookup on RGBA color values after color matrix transformation. See glColorTable.

GL_POST_CONVOLUTION_COLOR_TABLE

If enabled, preform a color table lookup on RGBA color values after convolution. See glColorTable.

	GL_RESCALE_NORMAL		If enabled, normal vectors specified with glNormal are scaled to unit length after transformation. See glNormal.
	GL_SEPARABLE_2D		If enabled, perform a two-dimensional convolution operation using a separable convolution filter on incoming RGBA color values. See glSeparableFilter2D.
	GL_SCISSOR_TEST		If enabled, discard fragments that are outside the scissor rectangle. See glScissor.
	GL_STENCIL_TEST		If enabled, do stencil testing and update the stencil buffer. See glStencilFunc and glStencilOp.
	GL_TEXTURE_1D		If enabled, one-dimensional texturing is performed (unless two- or three-dimensional texturing is also enabled). See glTexImage1D.
	GL_TEXTURE_2D		If enabled, two-dimensional texturing is performed (unless three-dimensional texturing is also enabled). See glTexImage2D.
	GL_TEXTURE_3D		If enabled, three-dimensional texturing is performed. See glTexImage3D.
	GL_TEXTURE_GEN_Q		If enabled, the q texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current q texture coordinate is used. See glTexGen.
	GL_TEXTURE_GEN_R		If enabled, the r texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current r texture coordinate is used. See glTexGen.
	GL_TEXTURE_GEN_S		If enabled, the s texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current s texture coordinate is used. See glTexGen.
	GL_TEXTURE_GEN_T		If enabled, the t texture coordinate is computed using the texture generation function defined with glTexGen. Otherwise, the current t texture coordinate is used. See glTexGen.

NOTES

GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE, GL_POLYGON_OFFSET_POINT, GL_COLOR_LOGIC_OP, and GL_INDEX_LOGIC_OP are available only if the GL version is 1.1 or greater.

GL_RESCALE_NORMAL, and GL_TEXTURE_3D are available only if the GL version is 1.2 or greater.

GL_COLOR_TABLE, GL_CONVOLUTION_1D, GL_CONVOLUTION_2D, GL_HISTOGRAM, GL_MINMAX, GL_POST_COLOR_MATRIX_COLOR_TABLE, GL_POST_CONVOLUTION_COLOR_TABLE, and GL_SEPARABLE_2D are available only if GL_ARB_imaging is returned from glGet with an argument of GL_EXTENSIONS.

If GL_ARB_multitexture is supported, GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_3D, GL_TEXTURE_GEN_S, GL_TEXTURE_GEN_T, GL_TEXTURE_GEN_R, and GL_TEXTURE_GEN_Q enable or disable the respective state for the active texture unit specified with glActiveTextureARB.

ERRORS

GL_INVALID_ENUM is generated if cap is not one of the values listed previously.

GL_INVALID_OPERATION is generated if glEnable or glDisable is executed between the execution of glBegin and the corresponding execution of glEnd.

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